Patent GB-577346-A (GB)
Title: Machines for the production of phonographic recording discs
IPC: B29D17/00
Filed: 1941-02-25
Abstract: 577,346. Coating blanks or discs. SOC. DES VERNIS PYROLAC. Feb. 25, 1941, No. 2553. Convention date, Feb. 9, 1939. [Class 95] In a machine for coating blanks or discs and in which varnish is dropped upon the discs which are carried on a conveyer belt, this belt is centred on the machine table by movable rollers, and a cleaning device for the discs is arranged in advance of the coating station and the discs are removed from the belt by means of a rotatable drum. In the drawings a table 3 (Fig. 2) is mounted on a framework 4 supported by uprights 5 and 6 connected by a member 7 carrying a bearing 8 for a roller 10 for used paper conveyer belt and a bearing 9 for a roller 11 which drives the paper belt at a constant speed. The driving pulley 11b transmits rotary movement to roller 10 through a belt 12 over pulleys 11a and 10a. Slipping of the belt 12 can occur through a winding-member 13 with an adjustable counter weight mounted on the part of the belt which is tensional. The drum 14 delivering the paper band is mounted on spindle 15 mounted in notches 16 of support 17 which may be moved laterally by threaded rod 17a. The paper band passes over table 3 after passing over tensioning bars 18 and 19: two screws 20 are provided at the ends of bar 19 for adjusting the position of said bar and to centre the paper band. The band then passes round rollers 24 and 25, the latter being mounted on frame 25a which oscillates about a vertical pivot 25b (Fig. 5). Since this roller is pivotable in one of the planes of the paper the tensions are balanced and the band automatically centred axially of the machine. At the front end of the varnish distributing device is a roller 60 faced with felt which moistens the disc with a "wett:ng agent" (anhydrous alcohol). The roller 60 is mounted in bearings on brackets 61 and 62 connected to table 3. These brackets have vertical slots 63 and 64 (Fig. 2) supporting scrapers covered with a spongy cloth to absorb excess of wetting liquid. Above roller 60 is a distributor 65 for feeding the liquid, drop by drop to roller 60. This distributor 65 is connected to a reservoir. A scraper 21 removes excess of coating material. Fig. 5 shows the device for removal of the coated discs arriving at the end of table 3. The disc is received by drum 69 on spindle 70a rotated by cable 71 over pulley 70 and over roller 25. The diameter of 70 is such that drum 69 revolves once in the time needed to coat one disc. Cable 71 is constantly tensioned by weight 73 on pulley 74. Drum 69 has two twin wheels carrying cam 69a which lifts the disc and draws it forward to a small roller 79 at the end of arm 80 pivoted at 81 on the frame of the machine and adjustable in height with respect to drum 69 by set screw 82 bearing against abutment 83 fixed on frame of machine, said screw 82 passing through nut 80a rigid with oscillating lever 80. The coating device is of known type allowing for adjustment of the thickness of the coating, having a constant feed device and having means for preventing flow of liquid when the machine is stopped. Specification 432,335 is referred to.